*
* For licensing information, see the file 'LICENCE' in this directory.
*
- * $Id: symlink.c,v 1.14 2004/11/16 20:36:12 dwmw2 Exp $
+ * $Id: symlink.c,v 1.19 2005/11/07 11:14:42 gleixner Exp $
*
*/
#include <linux/namei.h>
#include "nodelist.h"
-static int jffs2_follow_link(struct dentry *dentry, struct nameidata *nd);
-static void jffs2_put_link(struct dentry *dentry, struct nameidata *nd);
+static void *jffs2_follow_link(struct dentry *dentry, struct nameidata *nd);
struct inode_operations jffs2_symlink_inode_operations =
-{
+{
.readlink = generic_readlink,
.follow_link = jffs2_follow_link,
- .put_link = jffs2_put_link,
- .setattr = jffs2_setattr
+ .permission = jffs2_permission,
+ .setattr = jffs2_setattr,
+ .setxattr = jffs2_setxattr,
+ .getxattr = jffs2_getxattr,
+ .listxattr = jffs2_listxattr,
+ .removexattr = jffs2_removexattr
};
-static int jffs2_follow_link(struct dentry *dentry, struct nameidata *nd)
+static void *jffs2_follow_link(struct dentry *dentry, struct nameidata *nd)
{
- unsigned char *buf;
- buf = jffs2_getlink(JFFS2_SB_INFO(dentry->d_inode->i_sb), JFFS2_INODE_INFO(dentry->d_inode));
- nd_set_link(nd, buf);
- return 0;
-}
+ struct jffs2_inode_info *f = JFFS2_INODE_INFO(dentry->d_inode);
+ char *p = (char *)f->target;
-static void jffs2_put_link(struct dentry *dentry, struct nameidata *nd)
-{
- char *s = nd_get_link(nd);
- if (!IS_ERR(s))
- kfree(s);
+ /*
+ * We don't acquire the f->sem mutex here since the only data we
+ * use is f->target.
+ *
+ * 1. If we are here the inode has already built and f->target has
+ * to point to the target path.
+ * 2. Nobody uses f->target (if the inode is symlink's inode). The
+ * exception is inode freeing function which frees f->target. But
+ * it can't be called while we are here and before VFS has
+ * stopped using our f->target string which we provide by means of
+ * nd_set_link() call.
+ */
+
+ if (!p) {
+ printk(KERN_ERR "jffs2_follow_link(): can't find symlink target\n");
+ p = ERR_PTR(-EIO);
+ }
+ D1(printk(KERN_DEBUG "jffs2_follow_link(): target path is '%s'\n", (char *) f->target));
+
+ nd_set_link(nd, p);
+
+ /*
+ * We will unlock the f->sem mutex but VFS will use the f->target string. This is safe
+ * since the only way that may cause f->target to be changed is iput() operation.
+ * But VFS will not use f->target after iput() has been called.
+ */
+ return NULL;
}
+